A death by natural causes, as recorded by coroners and on death certificates and associated documents, is the end result of an illness or an internal malfunction of the body not directly caused by external forces, typically due to old age. This is especially true when an elderly person has several different conditions or diseases, but where it appears that none of them alone or together may clearly lead to the death, and it is uncertain which condition was the final factor causing death. For example, a person dying from complications from influenza (an infection), a heart attack (an internal body malfunction), or sudden heart failure would be listed as having died from natural causes. Health departments discourage listing old age as the cause of death because doing so does not benefit public health or medical research. Old age is not a scientifically recognized cause of death; there is always a more direct cause, although it may be unknown in certain cases and could be one of a number of aging-associated diseases.
By contrast, death caused by active intervention is called unnatural death. The "unnatural" causes are usually given as accident (implying no unreasonable voluntary risk), misadventure (an accident following a willful and dangerous risk, which can include drug or alcohol overdose), suicide, or homicide. In some settings, other categories may be added. For example, a prison may track the deaths of inmates caused by acute intoxication separately. Additionally, a cause of death can be recorded as "undetermined".